Antimicrobial material, obtained by adding one or more specific antimicrobial agents, is a kind of novel functional material which can inhibit or sterilize microbe. Since antimicrobial materials appeared in the market, they have developed quickly and become very popular because various synthetic materials and products are applied widely in everyday life. A CBS survey made in 1997 showed that people in Euro-American countries pay more and more great attention to the antimicrobial function of commodities. 52% of Americans will pay attention to whether the products they need have antimicrobial properties and deodorizing abilities when they purchase the commodities. The antimicrobial products are initially applied in the developed countries, such as Japan as well as Europe and America. It is since 1990's that the antimicrobial products have entered into a booming stage along with the fast development of economy and improvement of living standards in China. The development and application of the antimicrobial materials have become a green barrier to protect human health, which they have a great significance of improving living environment as well as diminishing the diseases of human being. Therefore, antimicrobial modification for various raw materials has become a new trend in material industries, thereof the antimicrobial products have great market demands and a prosperous future.
The prior technique of antimicrobial materials have come into practical application in the form of antibiotic fibre products since 1960s, and have been used in antimicrobial plastics since the early 1980s, since then they have experienced fast development with their application in various industries, such as chemical engineering, fibres, food, electrical appliance and cement, covering almost all major kinds of fibres and plastics products, such as Dacron, polypropylene fibres, Acrylon, PP, ABS, PE, and PVC, etc, Since 1990's, antimicrobial materials have developed into a giant industry.
Antimicrobial agents can be divided into three kinds according to their chemical composition; inorganic, organic and natural ones. As for the natural antimicrobial agents, they can not be industrialized for the limitation of sources and processing condition. With regard to organic antimicrobial agents, they have high efficiency and broad-spectrum antimicrobial ability, but they also have problems, such as poor thermal stability, toxicity, easiness of seepage and dissolution, short usage life time and poor wash resistance, so their application are greatly limited. Inorganic antimicrobial agents, particularly silver-series agents, characterized by safety, thermal stability, and durability, become widely applicable and acceptable antimicrobial agents in fibres, plastics and building materials with deficiency of higher price and slow-effectiveness. They can not be used efficiently like organic antimicrobial agents, moreover, they have poor effects on fungi and mould. Meanwhile, silver is chemically active, so is easily oxidized into silver oxide in brown color, leading to deteriorate the antimicrobial ability as well as stain on the appearance of the products. On the other hand, the poor compatibility of inorganic antimicrobial powder with macromolecular materials will cause agglomeration in matrix resin, resulting in difficulties in spinning and drawing. Inorganic antimicrobial agents play their role by releasing heavy metallic ions which are not conformable to the National Hygienic Standard concerning foods and packing materials, thereby mentioned agents can not be used in materials for food packing, kitchen wares and drinking water pipes, etc.
The British Patent GB 2,182,245 discloses polyhexamethylene biguanide being used as an antimicrobial agent. The same with this, polyhexamethylene biguanide used as decontaminant in water treatment, characterizing good water solubility and high safety for environmental protection are disclosed in Japanese Patents JP 05,209,195, JP 05,209,197, and JP 05,209,196.
U.S. Pat. No.4,891,423 discloses polyoxyethylenediamine biguanide being used as water-soluble antimicrobial liquor for contact lenses which proves that such an antimicrobial agent has a superior safety for human.
Russian Patent RU 2,052,453 and SU 1,750,979 disclose polyethylene diamine biguanide being used as an antimicrobial agent in water treatment and stuff added into pigment for oil painting protection.
In summary, polymer material containing guanidyl groups is a kind of effective antimicrobial agent, and can be used as water purificating agent because of its good water-soluble property. However, water-soluble property contrarily becomes retardation for its application as an antimicrobial modifier in the areas of plastics, fibres, rubber, and coating materials. Therefore, it is very important that further modification of the polymer containing guadinyl groups is needed in order to have more industrial value and wider application.